mirror of https://github.com/rust-lang/rust
20 lines
425 B
Rust
20 lines
425 B
Rust
//@ run-pass
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pub trait NumCast: Sized {
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fn from(i: i32) -> Option<Self>;
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}
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pub trait NumExt: PartialEq + PartialOrd + NumCast {}
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impl NumExt for f32 {}
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impl NumCast for f32 {
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fn from(i: i32) -> Option<f32> { Some(i as f32) }
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}
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fn num_eq_one<T: NumExt>(n: T) {
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println!("{}", n == NumCast::from(1).unwrap())
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}
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pub fn main() {
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num_eq_one(1f32); // you need to actually use the function to trigger the ICE
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}
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